Immunomodulation With Romiplostim in Young Adults With ITP

Thrombopoietin-receptor Agonist-immunomodulation in Young Adult Primary Immune Thrombocytopenia (ITP): A Multi-center Open Label Trial With Romiplostim

The study aims to investigate immunomodulatory effects of thrombopoietin-receptor Agonist (TPO-RA) in patients with primary ITP, who failed first-line therapy or who became intolerant to it. It is hypothesized that the early phase of this autoimmune disease may exhibit a stronger immunomodulatory potential in response to a stimulus, such as romiplostim. Such a process may subsequently be capable to induce regulatory mechanisms or tolerance.

Romiplostim (a thrombopoietin-receptor agonist, TPO-RA) will be administered subcutaneously once weekly over 22 weeks with a starting dose of 1mcg/kg body weight. The dose will be adjusted based on platelet counts as described in the summary of Product Characteristics (SmPC).

Inclusion Criteria:

• Informed consent as documented by signature (see informed consent form)
• Primary ITP according to the definition of Rodeghiero et al. (52) and a platelet count of <30x109/l
• Age range: 18-45 years
• Previously treated patients, with failure or intolerance to first-line therapy, or relapse after first-line therapy, i.e. corticosteroids, intravenous immunoglobulin (IVIG), or anti-D immunoglobulins

Exclusion Criteria:

• Adults older than 45 and children younger than 18 years
• Platelet count higher than 30x109/l at time of screening
• Suspicion of secondary ITP
• Positive family history for ITP
• Presence or history of autoimmune disease as judged by the investigator
• Hepatosplenomegaly
• Presence or history of relevant hepatic disease as judged by the investigator
• Presence or history of thromboembolic disease as judged by the investigator
• Patients with splenectomy
• Women who are pregnant or breast feeding
• Intention to become pregnant during the course of the study
• Lack of safe double contraception (see 7.1)
• Any vaccination 2 weeks prior start of the study
• Drugs with a known impact on the immune system or on platelet function must be recorded and an exclusion of the study should be discussed with the study center
• Known or suspected non-compliance, drug or alcohol abuse
• Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia of the study subject
• Participation in another study with investigational drug within the 30 days preceding and during the present study
• Previous enrolment into the current study
• Previous treatment with romiplostim or eltrombopag
• Hypersensitivity to the active substance or to any of the excipients or to E. coli derived proteins
• Enrolment of the investigator, his/her family members, employees and other dependent persons